System and method for identifying radiation in a contaminated room

ABSTRACT

A system for identifying the location of radioactive material in a contaminated room includes a projector, a distance sensor, and a CPU operably connected to the projector and distance sensor. The CPU receives distance data from the distance sensor and controls an image projected by the projector onto an object in the contaminated room. A method of identifying the location of radioactive material in a contaminated room includes conducting a radiation survey of the contaminated room and transferring information from the radiation survey to a projector. The method further includes placing the projector in the contaminated room and projecting information from the radiation survey onto an object in the contaminated room.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a divisional of U.S. application Ser. No.13/212,483, filed on Sep. 21, 2011, entitled “System and Method for theIdentification of Radiation in Contaminated Rooms,” which claimspriority to U.S. Provisional Application 61/401,718 filed on Aug. 18,2010, entitled “Position and Orientation Determination System for aRadiation Detector” and U.S. Provisional Application 61/403,813 filed onSep. 22, 2010, entitled “Hot Cell/Glovebox Characterization Using PODS™,RDDS™, BRACE™, and SourceMarker™,” the disclosures of which areincorporated herein by reference.

STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSOREDRESEARCH AND DEVELOPMENT

This invention was made with Government support under Contract No.DE-AC09-085R22470 awarded by the United States Department of Energy. TheGovernment has certain rights in the invention.

FIELD OF THE INVENTION

The present invention relates generally to the characterization of areassuch as shielded cells (hot cells), glove boxes, and rooms contaminatedby radioactive materials involving gamma-ray, alpha-particle and neutronemitters. More particularly, the present application involves adirectional shield, a position determination system, a back-projectedradiation analyzer and cell evaluator method, and a system for visuallyhighlighting contaminated areas on objects such as walls of acontaminated room.

BACKGROUND

The use of radioactive material may result in the contamination ofreactors, fuel and isotope processing facilities, laboratories, gloveboxes, isolators, and other rooms. Decontamination efforts of theserooms benefit from knowledge of where in the room radioactivecontamination is located. A worker may concentrate his or herdecontamination efforts on portions of the room that are actuallycontaminated while avoiding those areas that are already clean thussaving time, effort, money and exposure to radiation. Identification ofradioactive contamination in a room may be accomplished through the useof a collimator that includes a detector made of a radiosensitivedetector material that is in the shape of a sphere. The detector islocated within a collimator shield that has a series of throughapertures. The collimator may be placed within a room that iscontaminated with radioactive material for a time sufficient to allowportions of the detector to become opaque via exposure to the radiationcontamination.

The apertures of the collimator shield function to direct or channel theradiation into the spherical detector so that opaque lines or streaksare formed. The degree of opaqueness and the direction of the linesyield information on the intensity of the radiation and its direction.The collimator shield functions to block out radiation either completelyor partially so that portions of the detector are not turned opaque tobetter allow this determination.

The collimator is a passive device and thus cannot determine itsposition or orientation within the room. The user may remove thedetector and examine same in order to determine radiation intensity anddirection in much the same way that a medical professional will examinean X-ray. It may be the case that the sources of radiation that can betransferred through an aperture of the collimator shield are at tooremote an angle to the aperture. Such radiation may cause opaqueportions to be formed in association with the aperture that would beconfusing or tend to be interpreted as noise thus hindering accurateidentification of radiation intensity and location. Although techniquesare available for ascertaining the location and intensity of radiationcontamination within a room, such techniques are subjective in nature,costly, not efficient, limited in application, not automatic, andinaccurate. As such, there remains room for variation and improvement inthe art.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including thebest mode thereof, directed to one of ordinary skill in the art, is setforth more particularly in the remainder of the specification, whichmakes reference to the appended Figs. in which:

FIG. 1 is a top, plan view of a collimator in accordance with oneexemplary embodiment.

FIG. 2 is a side view of a directional shield in accordance with oneexemplary embodiment.

FIG. 3 is a cross-sectional view of a portion of the collimator of FIG.1.

FIG. 4 is a top view of FIG. 2.

FIG. 5 is a bottom view of FIG. 2.

FIG. 6 is a perspective view of a position determination system inaccordance with one exemplary embodiment.

FIG. 7A is a side elevation view partially in cross-section andschematic form of a position determination system in accordance withanother exemplary embodiment.

FIG. 7B is a side elevation view partially in cross-section andschematic form of a position determination system in accordance with adifferent exemplary embodiment.

FIG. 8 is perspective view of a position determination system with aremote controlled device in accordance with another exemplaryembodiment.

FIG. 9 is a perspective view of a position determination system with aremote controlled device and a vertical positioning system in accordancewith another exemplary embodiment.

FIG. 10 is a top plan view of a position determination system deployedinto a room in accordance with one exemplary embodiment.

FIG. 11 is a side elevation view of an apparatus used for obtainingradiation data from a detector.

FIG. 12 is a series of input steps for providing information to aback-projected radiation analyzer and cell evaluator method inaccordance with one exemplary embodiment.

FIG. 13 is a series of process steps for processing information in themethod noted in FIG. 12.

FIG. 14 is a series of output steps for outputting information in themethod noted in FIG. 12.

FIG. 15 is a line diagram illustrating a minimum fit line of data pointsof a ray-trace in accordance with one exemplary embodiment.

FIG. 16 is a mapping of radiation intensity on walls and a ceiling of acontaminated room.

FIG. 17 is a schematic drawing of an apparatus for executing aback-projected radiation analyzer and cell evaluator method inaccordance with one exemplary embodiment.

FIG. 18 is a perspective view of a visual illustration system disposedwithin a contaminated room in accordance with one exemplary embodiment.

FIG. 19 is a series of method steps for identifying the location ofradiation on an object in a contaminated room in accordance with anotherexemplary embodiment.

FIG. 20 is a schematic view of a visual illustration system inaccordance with another exemplary embodiment.

FIG. 21 is a schematic view of a visual illustration system inaccordance with a yet additional exemplary embodiment.

Repeat use of reference characters in the present specification anddrawings is intended to represent the same or analogous features orelements of the invention.

DETAILED DESCRIPTION OF REPRESENTATIVE EMBODIMENTS

Reference will now be made in detail to embodiments of the invention,one or more examples of which are illustrated in the drawings. Eachexample is provided by way of explanation of the invention, and notmeant as a limitation of the invention. For example, featuresillustrated or described as part of one embodiment can be used withanother embodiment to yield still a third embodiment. It is intendedthat the present invention include these and other modifications andvariations.

It is to be understood that the ranges mentioned herein include allranges located within the prescribed range. As such, all rangesmentioned herein include all sub-ranges included in the mentionedranges. For instance, a range from 100-200 also includes ranges from110-150, 170-190, and 153-162. Further, all limits mentioned hereininclude all other limits included in the mentioned limits. For instance,a limit of up to 7 also includes a limit of up to 5, up to 3, and up to4.5.

A collimator 10 can be used to measure intensity of radioactive materialin a contaminated room. The collimator 10 may include a detector 14 thatis made of a substance sensitive to radiation. Apertures 18 of thecollimator 10 function to channel the direction of radiation exposureonto the detector 14 into lines so that one may more easily ascertainthe location and intensity of present radiation.

FIG. 1 illustrates a collimator 10 that can be used in accordance withone exemplary embodiment of the invention. The collimator 10 may bespherical in shape and can have a collimator shield 12 made of agenerally thick and dense shielding material. A plurality of apertures18 extend through the collimator shield 12 and extend around the outersurface of the collimator 10. The apertures 18 may be positioned aroundthe entire outer surface of the collimator 10, or may extend around onlyportions of the outer surface while certain sections, such as thebottom, are not provided with apertures 18. Radiation, such as highenergy gamma rays, may extend through the apertures 18 and form streaksor otherwise discolored areas within a detector 14 located within thecollimator shield 12 for identification. The collimator 10 may include aplurality of directional shields 16 located at the apertures 18 for usein demarcating a field of view 22 to reduce noise that may otherwise bepresent within the detector 14 due to air gaps formed via the presenceof the apertures 18. The detector 14, along with other portions of thecollimator 10, may be as described in World Intellectual PropertyOrganization International Publication No. WO 2009/063246 A2, the entirecontents of which are incorporated by reference herein in their entiretyfor all purposes.

An exemplary embodiment of a directional shield 16 is illustrated withreference to FIGS. 2, 4 and 5. The directional shield 16 may be made outof the same material as the material making up the collimator shield 12.The directional shield 16 may thus resist the transfer of certain typesof radiation therethrough to the same extent as a comparable portion ofthe collimator shield 12. However, it is to be understood that in otherarrangements that the directional shield 16 may be made of material thatis more or less impervious to the transmission of various types ofradiation therethrough. The directional shield 16 may include a base 28that has an outer surface that is generally in the shape of a truncatedcone having its larger portion above its smaller portion. The base 28may be symmetrical about its axis which is also the axis 50 of thedirectional shield 16. Although described as being in the shape of atruncated cone, the bottom surface of the base 28 may be concave insteadof flat. As shown more clearly with reference to FIGS. 3 and 5, aconcave lower surface 30 of the base 28 is present and is symmetricalabout axis 50. The concave lower surface 30 may be present in order tobe complimentary to a curved outer surface of the collimator shield 12.In this regard, the concave lower surface 30 may match the curvature ofthe convex upper surface of the collimator shield 12 so that these twosurfaces fit against one another with no air gap therebetween. However,in other arrangements, the concave lower surface 30 need not be presentand the lower surface of the base 28 may be convex in shape or can beflat in shape.

An upper portion of the directional shield 16 may extend upwards fromthe base 28 and may have a concave outer surface 26 that is symmetricaland extends completely 360° about the axis 50. The concave outer surface26 has a shape that resembles a truncated cone, except for the fact thatits outer surface is concave. Upon extending away from the base 28, theradial size of the concave outer surface 26 and hence the upper portion25 decreases in size. The upper portion 25 demarcates the upper terminalend of the directional shield 16 at a top 24.

A stem 32 extends downwards from the base 28 and is cylindrical inshape. A bottom terminal end of the stem 32 opposite from the base 28defines the bottom 38 of the directional shield 16. The outer surface ofthe stem 32 is uniform and symmetrical in shape about axis 50. Thelongitudinal length of the stem 32 may be longer than the longitudinallengths of the upper portion 25 and base 28 combined. The variousportions of the direction shield 16 such as the upper portion 25, base28, and stem 32 may be integrally formed with one another and hence asingle piece, or may be multiple pieces connected to one another.Further, the upper portion 25, base 28, and stem 32 may all be made ofthe same material, or may be made of different material from one anotherin accordance with various exemplary embodiments. Further, althoughdisclosed as having an upper portion 25, base 28, and stem 32, it is tobe understood that additional components may be present in otherembodiments. Likewise, other versions of the directional shield 16 existin which one or more of the upper portion 25, base 28, and stem 32 arenot present.

With reference to FIGS. 3-5, it can be seen that the directional shield16 is hollow. An aperture extends all the way through the directionalshield 16 from the top 24 to the bottom 38. The aperture is made of twoconnected apertures 34 and 36. Aperture 34 is in the shape of atruncated cone with its larger portion located above its smallerportion. Aperture 34 extends from the top 24 through the upper portion25 and also through base 28. Aperture 34 is symmetric about axis 50. Theangle on the sides of aperture 34 is constant all the way through upperportion 25 and base 28.

Aperture 34 may terminate at the bottom of base 28 and may be incommunication with aperture 36. Aperture 36 is cylindrical in shape andextends from the top of the stem 32 adjacent base 28 to the bottom 38 ofthe directional shield 16. Aperture 36 may have a diameter that is thesame as the smallest diameter of the aperture 34 which is the diameterat the bottom of aperture 34. Aperture 36 is symmetrical in shape suchthat the sides of aperture 36 are located the same distance from theaxis 50 along their entire lengths from the top of stem 32 adjacent base28 to the bottom 38. As shown with reference to FIG. 3, if the sides ofaperture 34 were continued downward, they would intersect at a locationwithin aperture 36. This location may be one half of the way along thelongitudinal distance of the stem 32 along axis 50.

The directional shield 16 functions to provide a field of view 22 toallow radiation, such as gamma radiation, within the field of view 22 tobe imparted to the detector 14, while radiation, such as gammaradiation, outside of the field of view 22 is not imparted to thedetector 14. As such gamma radiation through the aperture 18 may beregulated so that only gamma radiation within the field of view 22 isimparted through the aperture 18 and those outside the field of view arenot imparted through aperture 18 into the detector 14. The directionalshield 16 functions to increase the amount of attenuating materialthickness based on the angle of incidence of the source of radiation.This configuration may afford a very abrupt transition point betweenin-field and out-of-field angles of incidence to allow for bothdetection of radiation and elimination of noise associated withradiation located at too remote an angle. As such, once the radiationsource is beyond the field of view 22, instead of having a continuousreduction in readings, the detector 14 reading will remain essentiallyconstant.

The collimator 10 is constructed so that there is an equal amount ofattenuating material between the detector 14 and the source of radiationat angles beyond the field of view 22. In other arrangements, a greateramount may be present. The additional attenuating material provided tothe detector 14 takes into account the “air gap” introduced by theaperture 18. The shape of the directional shield 16 is such that thetotal thickness of material through the center of the aperture 18 and atangles beyond the field of view 22 is equal to the thickness ofattenuating material in a solid (no aperture 18) sphere of attenuatingmaterial at the same angle.

As shown in FIG. 3, a radiation source 20 is present that is situated atan angle within the field of view 22 of the directional shield 16. Theaperture 34 is sized such that a first angle 42 extends from the axis 50to one side wall of the upper portion 25 and base 28, and such that asecond angle 44 extends from the axis 50 to an opposite side wall of theupper portion 25 and base 28 that is essentially in the oppositedirection. If the side walls of the upper portion 25 and base 28 wereextended, they would meet at a location in the stem 32 that would be theorigin 52 of the two angles 42 and 44. Addition of the two angles 42 and44 may yield the field of view 22 of the directional shield 16. Thefield of view 22 may be from 0°-45°, from 45°-90°, from 90°-120°, or upto 140° in accordance with various exemplary embodiments. Radiationsource 20 projects a path 46 towards the directional shield 16 that iswithin the field of view 22 such that the angle of path 46 with respectto the axis 50 through the origin 52 is less than angle 42. Radiationsource 20 will be “seen” by the detector 14 through the aperture 18 andbe noted by the detector 14.

A second radiation source 40 may be present and can be at a greaterangle of incidence than the first radiation source 20. Second radiationsource 40 may generate a path 48 towards the detector 14. Secondradiation source 40 may be at a location beyond the field of view 22such that the angle of path 48 through the origin 52 with respect to theaxis 50 is greater than that of angle 42. As shown, path 48 must gothrough some amount of the upper portion 25 and base 28 of thedirectional shield 16 before entering the aperture 18 and air gapassociated therewith. Further, the path 48 may extend through a portionof the material making up the stem 32 thus further attenuating theradiation. The presence of the directional shield 16 may preventradiation from the second radiation source 40 from reaching the detector14 through the air gap associated with the aperture 18. The detector 14will thus not record radiation of the second radiation source 40 throughthe aperture 18.

The dimensions of the directional shield 16 can be varied so that anysized field of view 22 is achieved. For instance, if the secondradiation source 40 and path 48 were angled from the axis 50 through theorigin 52 at an amount of 24° or greater then radiation from the secondradiation source 40 through the aperture 18 would not be visible to thedetector 14. In this arrangement, the first angle 42 would be 24°, andthe second angle 44 could be a similar amount (24°) so that the field ofview 22 would be 48°. With such an arrangement, if the first radiationsource 20 and path 46 were situated at an angle of 12° from axis 50through the origin 52 then it would be sensed by the detector 14 throughthe aperture 18.

The shape of the directional shield 16 may be dependant on the diameterof the aperture 18, the shape of the collimator shield 12 such as planaror spherical, and the desired field of view 22. The collimator shield 12may have an outer surface 54 that is convex in shape and an innersurface that is closer to the detector 14 and is concave in shape. Theaperture 18 can be selected so that it is of a diameter that provides adesired line of sight. This line of sight can be selected so that verylow energy gammas will still generate a dose rate into the detector 14up to the maximum desired field of view 22. Next, starting at the 2Dcenter of the aperture 18 the length of the air gap through the aperture18 at angles beyond the field of view 22 can be determined. This allowsfor the determination of the amount of additional attenuating materialneeded on the outside of the aperture 18. This additional material canbe added radially around the aperture 18 to produce a symmetric shapearound aperture 18. With the directional shield 16 in place and with asecond radiation source 40 outside the desired field of view 22, thedetector 14 material in line with the aperture 18 and the secondradiation source 40 has a similar amount of attenuating material to thesecond radiation source 40 as the neighboring detector 14 material underthe solid portion of the collimator shield 12.

The directional shield 16 can be included with all of the apertures 18of the collimator shield 12, or may be included with less than all ofthe apertures 18. The directional shield 16 may work with any collimatorshield 12 material type, collimator shield 12 thickness, aperture 18diameters, and field of view 22. If the attenuating properties of thedirectional shield 16 do not match that of the collimator shield, thethickness of the directional shield 16 as measured radially from theaxis 50 may be increased or decreased to match the attenuatingproperties of the solid portion of the collimator shield 12.

The detector 14 may not contain electronics or other mechanisms capableof determining its location and orientation within a contaminated room.A position determination system 100 may be provided in order to helpascertain the location and orientation of the collimator 10 within aroom. One exemplary embodiment of a position determination system 100 isillustrated in FIG. 6. The position determination system 100 may have abase 130 that may measure approximately 8″×8″ such that the footprint ofthe position determination system 100 is 8″×8″. The height of theposition determination system 100 may be 16″ in accordance with certainexemplary embodiments. An LCD screen 122 is located on a side of thebase 130 and may be touch sensitive so that the user can cycle throughmenus to obtain information and issue commands to the positiondetermination system 100. A distance sensor 112 is included and iscapable of rotating 360° about the position determination system 100.The distance sensor 112 is used in order to determine the distance fromthe position determination system 100 to a wall or other surface.Although described as being a distance sensor 112, it is to beunderstood that the sensor 112 may be variously configured in otherarrangements. The distance sensor 112 may be an ultrasonic sensor in oneembodiment. In another embodiment, sensor 112 may be a laser sensor.

The distance sensor 112 is capable of rotating a distance of 360°without any obstruction in the way of the sensor 112 as it looks outwardfrom its center of rotation. The system 100 may be constructed so thatthe sensor 112 is afforded an unobstructed view about its entire rangeof motion. A collimator cover 102 is located at the top of the system100 and houses a collimator 10. Although covered, the collimator cover102 may allow certain types of radiation to pass therethrough so thatthe detector 14 can in fact record radiation presence and intensity. Thecollimator 10 may thus be afforded an unobstructed view by the system100 with respect to the radiation it is attempting to detect. Withreference now to FIG. 7A, a schematic drawing of one exemplaryembodiment of the system 100 is shown. The collimator 10 includes a base11 that may be non-removably attached to the collimator shield 12. Thecollimator shield 12 can be disassembled such that its upper hemispherecan be removed from its lower hemisphere to access the detector 14located within. The collimator cover 102 can surround the collimator 10such that no portion of the collimator 10 is visible from outside of thecollimator cover 102. The collimator 10 and collimator cover 102 can bearranged so that they do not rotate with respect to base 130. In thisregard, a main shaft 104 may extend from the base 130 and can supportthe collimator 10 and collimator cover 102. The main shaft 104 can bearranged so that it does not rotate but is instead rigidly attached tothe base 130.

The distance sensor 112 can be rendered rotatable in a variety ofmanners. One such method is shown in FIG. 7A in which a rotating disk108 is present and is rotatably mounted onto the main shaft 104 by wayof a bearing 106. A mount 114 extends from the rotating disk 108, andthe distance sensor 112 is attached to the end of the mount 114. Thedistance sensor 112 may be in wireless communication with a CPU 120(central processing unit) or can be in communication therewith through awired connection. A planetary gear arrangement 110 may be used to driverotation of the rotating disk 108. The detector 14 may be locatedcompletely above the planetary gear arrangement 110. The planetary geararrangement 110 may include an outer gear 111 that is rigidly attachedto the bottom of the rotating disk 108. The outer gear 111 has gearingon its inner surface and can extend for 360° about the inner surface ofthe outer gear 111. A planetary gear 116 engages the gearing of theouter gear 111 and is driven by a stepper motor 118. The planetary gear116 may be located so that it is not coaxial with the outer gear 111 andmay be a pinion of the stepper motor 118. The planetary gear 116 isrigidly connected to the drive shaft of the stepper motor 118 so thatrotation of the drive shaft causes a corresponding rotation of theplanetary gear 116 which in turn causes rotation of the outer gear 111through its geared arrangement. Since the distance sensor 112 is rigidlyattached to the outer gear 111, it will be rotated as well upon rotationof the outer gear 111.

The distance sensor 112 may thus be rotated about the stationary mainshaft 104. The main shaft 104 and stepper motor 118 may both be mountedonto the base 130, and in the schematic diagram shown are mounted to atop plate of the base 130. Other mounting positions may be made in otherarrangements. The position determination system 100 includes additionalcomponents that may be mounted or located in or on the base 130. A CPU120 may be powered by a lithium-polymer battery 126. The battery 126 maybe strong enough to power the system 100 so that it can determine thelocation and orientation of the detector 14 and store this data to anon-volatile memory 128 or otherwise transfer this data to a remotelocation. The lithium-polymer battery 126 may be capable of running thesystem 100 for 8 hours in accordance with certain exemplary embodiments.

A digital compass 124 can be in communication with the CPU 120.Non-volatile memory 128 may likewise be in communication with the CPU120 in order to store data generated by the position determinationsystem 100. The LCD screen 122 may be in communication with the CPU 120in order to both display output from the CPU 120 and to input commandsfrom the user into the CPU 120. It is to be understood that thecomponents shown in communication with the CPU 120 may also be incommunication with one another directly, or through CPU 120, in otherexemplary embodiments. Further, the stepper motor 118 and distancesensor 112 may be controlled by the CPU 120 and may send informationback to the CPU 120. The various communications between the variouscomponents of the position determination system 100 may be accomplishedthrough hard wired and/or wireless connections.

Although described as having the detector 14 above the rotating disk108, and generally vertically higher than the distance sensor 112, otherarrangements are possible in which the detector 14 is located completelybelow the rotating disk 108 and completely vertically lower than thedistance sensor 112. In still other versions, the distance sensor 112can be located vertically at the midpoint of the detector 14 and canrotate around the midpoint of the detector 14.

The system 100 can be variously configured so that it is capable ofdetermining the distance from any component of the system 100 to thewalls of the room the system 100 is in, or to objects located within theroom. During rotation of the distance sensor 112, the software of thesystem 100 constantly monitors the distance data to determine the angleto the closest wall. As shown in FIG. 10, the distance sensor 112 mayemit a cone shaped sound wave 142 to search for objects 140. The object140 shown as being located is a wall 140, although the object 140 couldbe a chair, glovebox, computer, or any other object in otherarrangements. The range of the cone of the distance sensor 112 may befrom 20-765 centimeters. Due to this cone shape, and the distancesensor's one centimeter accuracy, it will report the same distance tothe closest wall some distance before and after the actual closest pointas it moves a specific angle. The true closest distance is half of thisangle and is the point on the wall perpendicular to the distancesensor's 112 center line. This position is the one reported by thesystem's 100 software. With reference back to FIG. 7A in addition toFIG. 10, after completion of the scan, the distance sensor 112 is movedto point to the closest wall 140 and the compass angle reported by thedigital compass 124 and distance to a point 141 of the wall 140 that isclosest to the detector are displayed on the LCD screen 122 along withthe digital compass 124 angle of the detector 14 orientation line 138. A0° reference line 125 of the digital compass 124 can be noted and thevarious compass angles to the orientation line 138 and objects 140, suchas the compass angle of the closest point 141 of wall 140, can bemeasured from this reference line 125. The distance sensor 112 may thenrotate to a wall 90° from this angle, that is the angle of the closestwall, and the distance can be measured and displayed along with thedigital compass 124 angle and distance. This second object 144 may be asecond wall 144 that is 90° to the first wall 140 and a point 146 of thesecond wall 144 may be the distance that is measured by the system 100.The angular orientation of the point 146 of the second wall 144 may alsobe measured by the system 100 and reported along with the distance. Theposition and orientation information is stored on the non-volatilememory 128 for later retrieval, and can remain ready for subsequentretrieval even if the lithium-polymer battery 126 dies.

The compass angle of the various points and lines may be an angle thatinforms one of the pitch and roll location of the points and lines. Asshown in FIG. 10, a top view of a room is shown and the pitch and rolldirections are the X-Y coordinates of the room such that the compassangle represents an orientation in a plane of the room. The orientationmay also include the heading. The heading is the Z direction/up downdirection in the room. It may be assumed in most instances that theorientation line 138 and other points and lines are horizontal so thatthey do not have a component in the Z or up/down direction. The compassangle would then yield the full orientation (heading, pitch, and roll)of the point or location. However, in other embodiments, the orientationline 138 may be pointed in an upward or downward direction so that itsproper orientation must include a component in the X, Y and Zdirections. The digital compass 124 may measure this component in the Zor up/down direction. As used therein the term angular position maysimply be a position of an object 140 or line in the pitch and rolldirection knowing that its heading is 0° or horizontal. However, theterm angular position may also refer to the position of an object 140 orline in which the heading, pitch, and roll all have some component or inwhich one or more of them have a 0 component. As used herein, the termorientation may refer to the heading, pitch, and roll of the line orobject. The term compass angle may refer to only two of the axes as thethird, for example the heading, may be understood to be 0 or horizontal.However, the term compass angle may in other arrangements refer to theheading, pitch, and roll such that all of these have some component orin which one or more of them have a 0 component. The digital compass 124or some other device may be used to determine the heading, pitch, androll orientation. As such, the X, Y, and Z directional orientation ofthe orientation line 138, objects 140, closest points 141, or otherobjects 140, lines or points may be determined.

The system 100 may recognize two special cases. The first special casemay be when the detector 14 is placed equidistant between two walls. Inthis case, the system 100 must be able to separate measurement data todistinguish between the two walls. The second special case may be whenthe closest distance to a wall is at the start of the scan or is at theend of the scan. This situation results in the home position pointingtowards the closest wall, and results in having to combine data from thestart and end of the scan in order to find the correct perpendicularangle to the wall.

The position determination system 100 may be set up so that when firstturned on, a screen appears on the LCD screen 122 that gives theoperator the ability to choose a “Count Down Time.” This “Count DownTime” introduces a time delay during which the system 100 can bedeployed remotely via a crane, robot, etc. before it starts a scan.After the count down delay, the CPU 120 reads the digital compass 124 torecord the orientation (heading, pitch, and roll) of the collimator 10and included detector 14. This position may be classified as the “homeposition.” The CPU 120 then takes distance sensor 112 readings as thestepper motor 118 rotates the sensor 112 in very small increments (forexample 1° increments). This data will indicate the distance from thewalls or objects to the center of the position determination system 100.Once a 360° scan is complete, software run by the CPU 120 saves thedistance data and performs a wall finding algorithm to determine theperpendicular distance, which may be from the center of the system 100to each detected wall, and the corresponding compass angle. The walldistances, compass angles and the orientation information are used alongwith the detector 14 data in order to map the detector's data on thewalls, floor and ceiling. All data is stored to the non-volatile memory128 which may be a secure digital memory card.

An exemplary embodiment for one algorithm performed by all or certaincomponents of the system 100 for use in finding walls may be as follows:

-   -   1. The captured scan data is in polar form (angle, distance), so        it must be converted to Cartesian (rectangular) coordinates (x,        y). As this is being done, the greatest polar distance is noted        and the corresponding Cartesian coordinate (called the “furthest        point”) is saved for later use.    -   2. This “furthest point” is near a corner, so it is a good        starting point for the algorithm.    -   3. Select the next N points to be processed. A moving set of N        points will be generated as the distance sensor 112 moves across        the wall. Each time a set of N points is processed, it contains        N−1 points from the previous time with only one new point. One        point is dropped and one is added to each new set of N points.        The following line (y=mx+b) for the current N points may be        calculated in which:        -   a. Slope=m: is determined through linear regression        -   b. Y Intercept=b: is determined through linear regression        -   c. Correlation Coefficient=R²        -   d. Perpendicular distance from the center of the position            determination system 100 (X=0, Y=0) to the line above.    -   4. If R² is greater than or equal to the “R² Threshold”, then        the set of points fit well to a line and form the “current wall        segment.”        -   a. If the last set of points is a wall segment, then the            “current wall segment” is part of that same wall segment. In            this case, the new point will be added to the last wall            segment, and a recalculation of the statistics will be            performed.        -   b. If the last set of points is NOT a wall segment, then a            determination is made to ascertain if the “current wall            segment” is on the same line as an “old wall segment”. This            may be done by comparing the slope and y-intercept of all            “old wall segments” to the “current wall segment”.            -   i. If an “old wall segment” and the “current wall                segment” are part of the same line, then the points of                the “current wall segment” are added to the points of                the “old wall segment”, and the statistics are                recalculated.            -   ii. If the “old wall segment” and “current wall segment”                are not on the same line, then the “current wall                segment” points are placed in a “new wall segment” and                the statistics are recalculated.    -   5. If R² is less than the “R² Threshold”, then the set of points        did not fit well to a line. An indication may be made that the        last set of points is not a wall segment.    -   6. If all points have been processed, go to step 7, else go to        Step 3.    -   7. All of the wall segments must be searched to find the true        walls.        -   a. Sort all wall segments by their slope to obtain parallel            wall segments.        -   b. Sort parallel wall segments by their y-intercept to            obtain wall segments on each side of the room.        -   Sort each of the side wall segments by distance to find the            one that is furthest away which will be the true wall.    -   8. For each of the true walls found, calculate the compass angle        in degrees of a line from the center of the system 100 [the        origin (0,0)] and perpendicular to the true wall. At this point        the algorithm has already calculated the distance from (0,0) to        the wall.        -   a. Calculate the equation of the line through point (0,0)            that is perpendicular to the true wall line.            -   i. Find the perpendicular slope (m_(p)): This slope is                the negative reciprocal of the true wall slope (m_(t)):                m_(p)=−1/m_(t)            -   ii. Use the Point-Slope Line Form to find the equation                of the perpendicular line y−y₁=m_(p)(x−x₁). Here                (x₁,y₁)=(0,0), and the equation is y=m_(p)x        -   b. Calculate the intersection point of the true wall line            (y=m_(t)x+b_(t)) and the perpendicular line through (0,0).            -   i. Set the equation of the true wall line equal to that                of the perpendicular line and solve for x.                -   1. m_(p)x=m_(t)x+b_(t)                -   2. (m_(p)−m_(t))x=b_(t)                -   3. x=b_(t)/(m_(p)−m_(t))            -   ii. Substitute the x value into one of the line                equations to find y. The equation that may be used for                this is y=m_(p)x.        -   c. Use the A tan 2(x,y) function to calculate the angle θ            from (0,0) to the intersection point (x,y). This calculation            will result in an answer that will be −π≦θ≦π, where θ is in            radians.        -   d. Convert radians to degrees: degrees=radians*(180/π)    -   9. Therefore, for each true wall, the algorithm has determined        the perpendicular distance from the origin to the wall, and the        compass angle.

It is to be understood that the aforementioned algorithm for determiningthe perpendicular distance from the origin to the wall and the compassangle is only exemplary and that other algorithms for ascertaining thisinformation may be possible. The algorithm can be carried out by anyportion of the system 100 such as the CPU 120, digital compass 124, LCDscreen 122, distance sensor 112, rotating disk 108, stepper motor 118,and non-volatile memory 128. These components need not be used in otheralgorithms for use in obtaining the aforementioned information. Thedistance and angular readings may be used to determine the location andorientation of the detector 14, collimator 10, and/or system 100 withinthe room. As such, the measurements may be applicable to any of theportions of the system 100, including the carried collimator 10 anddetector 14.

The various measurements may be thought of as having the positiondetermination system 100 as its origin. As such, if an object 140 ismeasured to be five feet, it will be five feet from the positiondetermination system 100. However, it may be the case that a moreprecise origin is desired than the position determination system 100 ingeneral. For example, the origin may be defined as being a center 15 ofthe detector 14. The detector 14 in one embodiment may be aradiosensitive detector material that is in the shape of a sphere thatis sensitive to radiation, and the center 15 may be the physical centerof this sphere. In other embodiments, the origin may be a face 113 ofthe distance sensor 112, a longitudinal axis of the main shaft 104, acenter of rotation 109 of the rotating disk 108, or a mark or otherlocation on the base 130 such as a center 131 of the base 130. Any partof the system 100 may be the origin in yet other arrangements.

The detector 14, collimator 10, and/or position determination system 100may have an orientation line 138. This line can be etched or otherwisenoted on the collimator 10, detector 14, base 11, collimator cover 102,or any other portion of the system 100. This orientation line 138 mayhelp to properly orient the detector 14 and collimator 10 with respectto the system 100 and/or the room into which it is placed. A readingfrom the digital compass 124 may indicate to which wall in the room theorientation line 138 is pointing. The orientation line 138 may bematched with a mark on the collimator cover 102 or other portion of thesystem 100 so that the proper positioning of the detector 14 is notedupon determining the wall and angular orientations via the algorithm.Since the relative position between a face 113 of the distance sensor112 and the center 15 of the detector is known, the system 100 mayfunction to determine the location of the center 15 of the detector 14relative to the walls of the room it is in and the angle the orientationline 138 is pointing to in the room.

It is to be understood that the arrangement illustrated in FIG. 7A ofthe position determination system 100 is only exemplary and that othersare possible in accordance with other exemplary embodiments. Forexample, FIG. 7B discloses an alternative arrangement of the positiondetermination system 100 in which the planetary gear arrangement 110 isvaried from that shown in FIG. 7A. The stepper motor 118 is centrallylocated so that the pinion 116 rotates about a central axis of theposition determination system 100 and is coaxial or in line with thecenter 15 of the detector 14. A main shaft 104 located at the center ofthe system 100 is not present. The pinion 116 rotates and in turn drivesan idler gear 115 that is mounted to the base 130. An outer gear 111engages the idler gear 115 and is driven by the idler gear 115. Theouter gear 111 is rigidly attached to the rotating disk 108.

A bearing 106 is present and the rotating disk 108 is mounted thereon sothat the rotating disk 108 can rotate with respect to the base 130. Apair of main shafts 104 may be included and may be arranged to allow thecollimator 10, base 11, and collimator cover 102 to remain stationaryand thus rigidly attached to base 130 while the rotating disk 108 andsensor 112 rotate relative to the base 130 and the collimator cover 102.In other exemplary embodiments, the collimator 10, base 11, andcollimator cover 102 are rigidly attached to the rotating disk 108 andthus rotate with respect to the base 130. Although not shown in FIG. 7B,the CPU 120, LCD screen 122, digital compass 124, lithium-polymerbattery 126, and non-volatile memory 128 may also be present. Thevarious components of the position determination system 100 may functionand be arranged as those previously described with the embodiment ofFIG. 7A and thus a repeat of this information is not necessary.

The walls 140 described as the objects that are measured may be the sidewalls of a room into which the position determination system 100 isdeployed. The position determination system 100 may be capable ofdetecting distances and orientations associated with the ceiling andfloor of the room into which the position determination system 100 islocated. Here, the distance sensor 112 may project sound waves onto thefloor and ceiling in order to measure the floor and ceiling in a similarmanner as previously described. As such, as used herein the objects 140may include walls 140 of a room, and the walls 140 may include the sidewalls, ceiling, and/or floor in accordance with various exemplaryembodiments. It is therefore the case that the term objects is broadenough to include walls and the term walls is broad enough to includeceilings and floors. In yet other arrangements, knowledge of theposition and orientation of the side walls 140 allows the positiondetermination system 100 to infer the location and orientation of thefloor and ceiling because these two surfaces are contiguous with theside walls 140 of the room on all of their sides. As such, in otherembodiments of the position determination system, the distance sensor112 does not directly measure the ceiling and floor of the room.

Although described as being used in connection with a detector 14, thesystem 100 may be used without the detector 14 and/or collimator 10 todetermine wall and object distance and angular data. Other items, suchas a camera or chemical detector, may be used in place of the detector14 and/or collimator 10 in other exemplary embodiments. For example, thesystem 100 can be used in conjunction with any item or method in whichdata concerning position and/or orientation within a room is needed.

The position determination system 100 can be placed into a room in avariety of manners. One such deployment is shown in FIG. 8 in which aremote controlled device 132 is used to position the system 100 to adesired location within a room. The remote controlled device 132 has apair of tracks that can be remotely controlled through either a wirelessconnection or a wired/tethered connection so that the user can move theremote controlled device 132 forwards or backwards. The tracks may alsobe used to turn the remote controlled device 132 so that the system 100can be moved to a desired position within the room without the userhaving to enter the room.

The system 100 may be mounted to an upper surface 134 of the remotecontrolled device 132. The height of the upper surface 134 to the floormay be known and can be incorporated into the algorithm to know theelevation of the distance sensor 112 and center of the detector 14. Thebase 130 may be mounted to the upper surface 134 through the use ofbolts or other mechanical fasteners or through a permanent/integralconnection. The system 100 can be located on the upper surface 134 whenthe system 100 is used to obtain distance and angular measurements.Alternatively, a crane or other device may be used to remove the system100 from the remote controlled device 132 before the measurements aretaken. The system 100 may thus be rendered mobile via the remotecontrolled device 132 to provide greater functionality.

An alternative exemplary embodiment is shown with reference to FIG. 9.Here, a remote controlled device 132 is present and can be movedremotely by the user as previously discussed. A vertical positioningsystem 136 extends upwards vertically from the upper surface 134. Thebase 130 of the position determination system 100 is mounted to the topof the vertical positioning system 136. The vertical positioning system136 is present in order to increase the height of the system 100 toplace the detector 14 and distance sensor 112 at an elevated location.Again, knowledge of the amount of elevation can be incorporated into thesystem 100 so that it knows its elevation from the floor. Elevation ofthe location of components of the system 100 such as the detector 14and/or distance sensor 112 may allow them to more easily view radiationand/or walls without being obstructed.

The vertical positioning system 136 can be rigid in natures such thatits height does not change. As shown, the vertical positioning system136 may include four columns, however it is to be understood that anynumber of members capable of elevating and supporting the system 100 canbe used. In other embodiments, the vertical positioning system 136 mayinclude one or more telescoping members that allow the user to adjustthe vertical positioning of the system 100. A motor, piston, or othermember can be attached to the upper surface 134, the base 130, and/or tothe vertical positioning system 136 to effect raising and lowering ofthe system 100.

A detector 14 may include material that provides a differential outputbased on exposure to radiation. This differential output may be changesin optical density, color, or temperature. The changes may also be inelectron shell configurations, chemical composition, or some otherphysical or chemical alteration based on radiation exposure. Thedetector 14 materials may be 3D or 2D, and this selection may depend onthe application, the means of extracting data, or on the final resultdesired. The materials of the detector 14 can be exposed bare or can becollimated to provide better directional sensitivity.

An automated method may be provided in order to extract source locationof radiation, energy of radiation, and radiation intensity from acollimated exposed detector 14 material. The method may work for nearlyany detector 14 material that can be read or scanned into a computerdata file, and the method may provide a 3D or 2D matrix of exposurevalues as integers or floating point numbers.

Input information may be obtained from the position determination system100 and/or the detector 14. In this regard, a user may place theposition determination system 100 with included detector 14 into a roomthat features some amount of radiation contamination. The room may be anisolator, a shielded cell, a glove box, or a fume hood in accordancewith various arrangements. After the position determination system 100has obtained its distance and orientation readings, and after thedetector has been exposed to the radiation for a sufficient amount oftime, the position determination system 100 and/or detector 14 may beremoved from the room for subsequent analysis.

One such apparatus for analyzing the detector 14 may be shown withreference to FIG. 11. Here, the detector 14 may be removed from thecollimator shield 12 and placed into an aquarium and rotation stage 204.Upon exposure to radiation, streaks 208 will be imparted into thedetector 14 material and will be more opaque when exposed to a greateramount of radiation. The streaks 208 will point to or otherwise be inthe direction of the radiation source or sources that contributed totheir creation. The detector 14 may thus yield information on theintensity and location of radiation sources. An optical-CT scan may beconducted as shown in FIG. 11 in order to withdraw information from thedetector 14. The detector 14 may be positioned between a telecentriclight source 202 and a telecentric lens 206, and the optical-CT scan mayreturn a matrix of radiation induced changes in optical attenuationcoefficients. The change in degree of opaqueness is proportional to thelocally absorbed does of radiation.

A back-projected radiation analyzer and cell evaluator method 200 willnow be described. Such method can be run on a computer and may becompletely automatic, or primarily automatic requiring a minimum ofhuman input. In other arrangements, the method 200 may require asignificant or substantial amount of human input. The method 200 willfirst require the input of certain information. FIG. 12 illustratesvarious input steps that may be performed in order to provide the method200 with processing information.

Step 210 includes the input of the shape, size, and collimationcharacteristics of the exposed material of the detector 14. The exposedmaterial of the detector 14 may be a spherical ball, and the diameter ofsuch detector 14 can be input along with any other physicalcharacteristics such as the size and location of any flat outer surfacesshould the detector 14 not be completely spherical. The radiosensitivedetector material characteristics of the detector 14 can be input if thedetector 14 is in fact of such a composition. Also, if more than onedetector 14 is used, the physical layout of this additional detector(s)may be provided to the method 200 as shown in step 212.

An additional input step 214 may be performed in which theradio-characteristics of the exposed material of the detector 14 areprovided to the method 200. These characteristics may be the output ofthe optical-CT scan of FIG. 11 in which the amount of opaque materialalong with its shape, direction, and intensity is determined. Input step216 may be performed in which the location and orientation of thedetector in the contaminated room is provided to the method 200. Thisinput may be the output of the position determination system 100 inwhich the distance and orientation (heading, pitch, roll) to an originand of an orientation line 138 are provided. The orientation line 138may correspond to a particular orientation of the detector 14 so thatthe particular orientation of the detector 14 in the contaminated roommay be determined.

An additional input to the method 200 may be provided as shown in step218 in which the dimensions of the contaminated room and the dimensionsof any large objects in the contaminated room are provided. The largeobjects may be those large enough to accumulate surface contaminationthereon. It is to be understood that the list of inputs in FIG. 12 isonly exemplary and that others may be added or some of those shown maybe deleted. For example, the location of the characterizer (origin pointdetermined) and the dimensions of the contaminated room and largeobjects may be omitted from being provided as input. In these instances,the method 200 may still function to provide proper output, but theprocessing time may increase due to the algorithm cycling through allpossible 3D locations in the contaminated room instead of just on thesurfaces of objects.

The method 200 may proceed to a series of processing steps shown forinstance in FIG. 13 in which the input data is analyzed by an algorithmthat can be carried out by a computer. In step 220, input data, forexample input information as previously discussed with reference to FIG.12, may be provided to the method 200. This input data may be data onthe contaminated cell and objects inside of the cell such as tables anddrums. The method 200 may cycle though every X,Y point on each wall andon the floor and/or ceiling depending upon the particular detector 14deployment orientation. The X,Y points that are processed may also beX,Y points located on objects within the contaminated room.

Moving to step 222, the method may then look at the current X,Y pointand determine whether an object is between the detector 14 and thepoint, and if so the point on the object closest to the detector 14 isused. The X,Y point on the wall (or object if applicable) is thenconverted to an X,Y,Z point in the contaminated room. In accordance withcertain exemplary embodiments, this step 222 is optional and need not beimplemented. Instead, the method 200 may move directly from step 220 tostep 224 without conducting step 222. The method 200 may then performstep 224 in which the method 200 determines which aperture 18 of thecollimator 10 has the X,Y,Z point just determined within theirparticular field of view 22. The particular fields of view 22 may beinput to the method 200 in a collimator editor of a software packageused to implement the method 200. This step 224 may be performed byknowing the location and collimation data of the characterizer.

The method 200 may then move onto step 226 in which for each aperture 18within the field of view 22 a ray-trace is generated. The ray-trace maybe a one-dimension array of exposure values obtained from the detector14 material by a linear scan through the 3D material of the detector 14or through layers of 2D material if such is used as the detector 14. Theray-trace may be generated through data obtained via analysis of thedetector 14, such as that obtained through the set-up of FIG. 11, andcan pass through the center of the aperture 18 and may terminate at theX,Y,Z coordinates of the point currently being evaluated. In certainembodiments, the ray-trace may extend from the center 15 of the detector14 through the center of the aperture 18 and to the X,Y,Z coordinates ofthe point currently being evaluated.

The method 200 may then perform a subsequent step 228 in which themaximum possible exposure that the ray-trace could have received isdetermined. With reference now to FIG. 15, a plot of the previouslygenerated ray-trace is shown in which the data points 230 represent theexposure value of the ray-trace in view of the distance from the X,Y,Zpoint to the origin (center 15) of the detector 14. It may be assumedthat the ray-trace has a continuous, although not necessarily linear,decrease in exposure as distance to the radiation source increases. Thetrack shape of the ray-trace may be examined and a minimum fit line 232or some other non-linear shape may be fitted to the ray-trace. Theminimum fit line 232 may be a linear line that runs through the minimumdips or values of the data points 230 such that none of the data points230 are located below the minimum fit line 232. The minimum fit line 232may provide a maximum possible exposure value and a rough idea of theradiation source energy based upon the track shape of the ray-trace. Theheight of the minimum fit line 232 above the reference zero exposurevalue may be the maximum possible activity of a source at the X,Y,Zpoint.

The X,Y,Z coordinate point is set to have a radioactivity level of theminimum possible exposure levels. This is because given a real source atthis 3D location, it will add an exposure amount equally to allapertures 18 within its field of view 22. The fact that some of theray-traces indicate a higher exposure can be attributed to noise andtracks from other radiation sources in the contaminated room. Statedanother way, there is no way for a radiation source of X intensity toproduce ray-traces with an exposure less than X, but it is possible forsome ray-traces to show exposure greater than X because of contributionsfrom other radiation sources. It is therefore the case that the valuedetermined is the maximum possible intensity of source at the 3Dlocation.

Step 228 could alternatively be performed such that for theone-dimensional array previously generated in step 226, the method 200calculates an inverse exponential fit line to the one-dimensional arraydata that is within the range of possible exposure energies. Thisminimum fit line provides the intensity of the radiation source based onthe initial magnitude of the minimum fit line, and the energy of thesource based upon the shape of the minimum fit line. From the list ofinverse exponential fit lines, the line with the minimum sourceintensity is selected. This intensity value and energy is assigned tothe X, Y point for the object/wall to which the ray-trace is directed.

The algorithm may make an assumption in order to extract valid andrelevant data from the detector 14 material. First, it is asserted thatthe detector 14 material will provide an inverse exponential response toa radiation field, along a line that is parallel to the direction of thesource. This assertion is assumed valid due to the nature of how allmatter shields gamma radiation. All matter will shield gamma radiationby an inverse exponential equation, with some constant attenuationcoefficient, over some variable distance. The detector 14 material willprovide a similar exponential attenuation of the gamma radiation as afunction of the distance traveled through the material. The magnitude ofthe exponential response is not only dependent on the material but alsoon the energy of the gamma radiation. Low energy gammas will be shieldedmuch more quickly through a material than higher energy gammas, but willstill provide an inverse exponential decrease. The speed at which thegammas are attenuated provides the “shape” data of the one-dimensionarray. This shape can be matched or interpolated to the input shape datato the algorithm to extract the energy of the source.

Calculation of the minimum inverse exponential line 232 may take intoaccount any noise through the material along this line from otherpossible sources in the environment. It is asserted that an actualsource in the direction of the line 232 will produce an inverseexponential line that cannot have any other “humps” or other anomaliesmidway through the line. The presence of any anomalies can be attributedto sources in other directions that are providing some radiationcontribution through a small section of the line. These “humps” can beeffectively ignored since an actual source in the direction of the linecannot produce a “hump” partially down the length of the line. Theresult of this analysis is a maximum possible intensity of a real sourcein the direction of the line and the likely energy of the source basedon the shape of the line. The intensity value may be the maximumpossible intensity of a real source in the direction of the line, andmay not necessarily be the actual intensity of the source. This isbecause it is possible for the entire line to be flooded with noise fromother sources in the environment. However, it is not possible for thesource to be of greater intensity than the value derived, otherwise themagnitude of the inverse exponential fit line would have been greater.

After determining the maximum possible intensity of each one-dimensionalarray through the multiple holes that are within the FOV of a particularpoint, the minimum intensity from this list may be chosen as theintensity of a source at the point. Again, this chosen value is themaximum possible intensity of a source at the point. As an example, aparticular point on a wall 140 has three collimator holes 18 within thefield of view 22, and the three minimum inverse exponential fit linesgive maximum possible source intensities of 100 mR/hr, 1000 mR/hr, and2000 mR/hr. If a real source were to be at the particular point on thewall 140, it would contribute the same total dose rate to each of thethree holes 18 equally. Because of the additive nature of radiation doseto the detector 14 material, it is not possible for one of the holes 18to indicate an exposure rate less than the actual source intensity, butit is possible for some of the holes 18 to indicate an exposure rategreater than the actual source intensity due to noise from other sourcesin the environment. In other words, an actual source on this point ofthe wall that has intensity of 1000 mR/hr could not leave a collimatorhole's 18 intensity value of <1000 mR/hr because the hole would beexposed to 1000 mR/hr at a minimum from this single source. Choosing theminimum intensity value of the list of collimator holes 18 within thefield of view 22 provides the maximum possible value of a real source atthe particular point.

The method 200 may move on to the next step 234 in which the method 200then repeats the procedure for every X,Y,Z point that is input into themethod 200. The steps 220, 222, 224 and 226 may be repeated for all X,Ypoints on each of the walls, ceiling and floor. Further, if objectsother than the walls, ceiling and floor are in the contaminated room,X,Y points on the objects may be processed as well. After thisprocessing, the method 200 may move onto the output stage as illustratedin FIG. 14.

The output of the method 200 may include a step 236 in which a series oftwo-dimensional images of the intensities at each X,Y point on the wall,ceiling, floor, and/or object are generated. Step 238 may also beperformed by the process 200 in which a series of two-dimensional imagesare generated of the energies at each X, Y point on the wall, ceiling,floor, and/or object. Further, the process 200 may generate a text filewith a specific format at step 240 that describes how to drawtwo-dimensional line drawings of the contaminated area on the walls,floor, ceiling, and/or objects.

Output of the method 200 may be illustrated as shown with respect toFIG. 16 in which radiation intensity is mapped on the walls and ceilingof a contaminated room in Sv/hr or any other desired dose rate unit.Although the floor is not illustrated, it may be mapped as well in otherembodiments, along with objects located within the contaminated room. Asshown, the radiation intensity is mapped such that a zone of lowradiation intensity 242, a zone of medium radiation intensity 244, and azone of high radiation intensity 246 is displayed. The various zones242, 244 and 246 may be displayed in the form of colors, and a legendshowing the strength of radiation intensity for the various colors maybe provided as well. The areas between the borders demarcating zones242, 244 and 246 may be filled with colors that show the variousradiation intensities and their transition from one zone to the next.Although not specifically shown in FIG. 16, the colors may vary instrength within each one of the particular zones 242, 244 or 246. Forexample, the color in zone 246 can be of different shades or intensitiesat various locations within the zone 246 to show that the radiation isof different, particular intensity at the particular location withinzone 246. As such, it is to be understood that the cross-hatching ofzones 242, 244 and 246 in FIG. 16 dictates that different colors orintensities of colors can be found even within each zone 242, 244 or 246to instruct one as to different locations and intensity of radiationwithin the zones 242, 244 and 246. It is to be understood that thegraphical output illustrated in FIG. 16 is only one possible way tooutput information generated by the process 200 and that others arepossible in accordance with other exemplary embodiments.

The method 200 may execute such that the only human interaction requiredis the input data as the processing steps in FIG. 13 and the outputsteps in FIG. 14 may be performed automatically by a CPU. Further, someof this input data may be automated as well. In addition, much of theinput data will remain constant for each characterization, specificallythe data on the characterizer device 100. The algorithm removes a humanelement from the in-depth processing, which reduces error and eliminatesthe “human opinion” that will vary from one analyst to another,providing consistent and reproducible results.

An apparatus 248 capable of implementing and performing the method 200is disclosed in FIG. 17. The apparatus 248 may include a CPU 250 thatcan be a processor of a computer and may include random access memory,data storage, and other hardware and software components. The apparatus248 may also include an input device 252 that may be a computer mouse,keyboard, disk drive, Internet connection, hard-wired connection,wireless connection, and/or computer screen. The CPU 250 may execute acollimator editor module 258 that can be manipulated by the user throughuse of the input device 252. The collimator editor module 258 maysimplify the entry of collimator shield 12 thickness and aperture 18data. A user-friendly 3D display of the data may be presented to theuser to give visual confirmation that the collimator 10 is designedcorrectly for accurate processing by the method 200. The user may enterother information relevant to the collimator 10 such as the fields ofview 22, collimator 10 dimensions, direction of orientation line 138,material making up the detector 14, shape of the detector 14, and/ordirectional shield 16 data. The various data may be automaticallytransferred to the apparatus 248 by, for example, the positiondetermination system 100 or by some other automatic input. However, thecollimator editor module 158 may allow the user to modify automaticallyinput data, to enter data that has not been automatically provided, orto verify the accuracy of input information.

Another module that may be run by the apparatus 248 is a cell editormodule 260 that can be run by the CPU 250 and that can be modified bythe input device 252. The cell editor module 260 allows the user tospecify contaminated room dimensions as well as adding large objects 140such as tables, drums and containers. A 3D display may be presented tothe user to allow him or her to verify the contaminated room inputinformation.

The CPU 250 and input device 252 may also be used to run and manipulatea detector projection module 262. This module 262 may allow the user tolocate the center 15 of the detector 14 in a raw scan file by looking atslices of the detector 14 from the top and sides. The module 262 maypresent the user with a screen in which he or she can rotate a data linethrough the center Z layer of the scan file to help determine the radiusof the detector 14 in the raw scan. The module 262 may allow him or herto define the track shape and amplitude that can be used to determinethe source activity and roughly source energy.

The input steps disclosed in FIG. 12 may be performed by the userthrough use of the input device 252 and CPU 250, or through just theinput device 252, or may be performed through an automatic transfer. Theprocessing steps disclosed in FIG. 13 may be performed automatically bythe CPU 250. The output steps disclosed in FIG. 14 may be implemented bybeing displayed on a display screen 256 and/or by being written to afile 254 or by being transferred in a variety of manners.

The collimator 10 with direction shields 16, the position determinationsystem 100, and the back-projected radiation analyzer and cell evaluatormethod 200 are capable of mapping radiation intensity onto objects 140such as tables, cabinets, walls, floors, and ceilings of the scannedarea in 3-D computer rendered models. A visual illustration system 300allows a user to view the detected radiation in real time in the actual,physical room from which the radiation measurements were taken. Such asystem 300 provides a mapping of the radiation onto the objects 140 sothat the user has knowledge of the actual locations of contamination andin certain arrangements knowledge of the intensity of such radiation.The user may focus his or her decontamination efforts on these areaswhile the system 300 identifies such areas, or the user may mark themfor subsequent decontamination without presence or running of the system300. The system 300 makes radiation visible, which otherwise wouldremain invisible.

With reference first to FIG. 18, the visual illustration system 300 isshown located inside of a contaminated room 302, which may be an actualphysical room into which radioactive contamination is present. Thevisual illustration system 300 creates a projected image 308 onto object140 which is a wall 304. The visual illustration system 300 may obtainoutput data from the method 200 and may include a laser projectionsystem that uses same to draw an outline around the contaminated areasof the wall 304. The projected image 308 may include an outermost linethat is a low radiation intensity boundary 310. Areas of the wall 304between the boundary 310 and a medium radiation intensity boundary 312may be contaminated with low intensity levels of radiation. These visualmarkers cue the user as to where the low intensity levels of radiationare in the contaminated room 302 so that they can decontaminate same.Additionally or alternatively, the user can mark this area of lowintensity radiation level on wall 304 so that it can be decontaminatedat a later date.

As disclosed, the visual illustration system 300 is used to identify thelocation, and possibly additionally the intensity, of radioactivematerial on the walls 304 of the room. However, it is to be understoodthat this use of the visual illustration system 300 is only exemplaryand that it need not be used to display the location of radioactivematerial location, and possibly intensity. The visual illustrationsystem 300 may be used in order to visually identify any type of 2D or3D sensor data obtained. It is therefore the case that the visualillustration system 300 may visually indicate the location of itemsother than radioactive material. The use of the visual illustrationsystem 300 with radioactive material location identification is only forsake of example and convenience.

As stated, the projected image 308 includes a medium radiation intensityboundary 312 that is surrounded by boundary 310. The area of the wall304 bounded by the boundary 312 and a high radiation intensity boundary314 is contaminated with radioactive materials with a medium radiationintensity level. The high radiation intensity boundary 314 completelyencloses a perimeter of the wall 304 that is contaminated with highintensity radiation levels. Although shown as having the high radiationintensity boundary 314 completely contained within the perimeter of themedium radiation intensity boundary 312, which is likewise completelycontained within the perimeter of the low radiation intensity boundary310, this is only exemplary and may be varied in other embodiments. Forexample, the high radiation intensity boundary 314 may surround one orboth of the low or medium radiation intensity boundaries 310 and/or 312.The areas between the boundary lines 310, 312 and 314 may not containlaser light such that they are blank or otherwise not filled in withlaser light. These areas may simply be devoid of any of the laser lightsuch that only the outlines of the boundary lines 310, 312 and 314 makeup the projected image 308. The user can use the boundaries 310, 312,and 314 to identify low, medium, and high intensity radiation levels onthe wall 304 so that these can be decontaminated. Additionally oralternatively, the user may mark the location of the radiation byphysically marking one or more of the boundaries 310, 312, and/or 314 onthe wall 304 so that this radiation can be later decontaminated. Thesystem 300 may function to project the boundaries 310, 312 and 314 aslines so that the areas between these lines 310, 312 and 314 are nototherwise filled in with any light or projections from the system 300.The boundary lines 310, 312 and 314 may all be of the same color, or maybe all different colors in accordance with various embodiments. Whenmade of different colors, the user may be more easily able todistinguish between the low, medium and high levels of radiation. Thesystem 300 can create a second projected image 316 onto a second object140 that may be a second wall 306 contacting and oriented at a 90° angleto the first wall 304. The second projected image 316 may include low,medium, and high radiation intensity boundaries as previously discussedwith respect to the first projected image 308 and a repeat of thisinformation is not necessary. The second projected image 308 mayindicate the presence of radiation on the second wall 306 and theintensity and shape of the contaminated area, and hence projected image316, may be different than that of the first projected image 308 sinceradiation on the two walls 304 and 306 may be located thereon indifferent amounts, areas, and shapes. The system 300 may utilize theoutput from steps 236, 238 and/or 240 from the method 200 in addition toorientation and/or location output from the position determinationsystem 100. The system 300 may generate the projected images 308 and 316via lasers in order to create the outlines around contaminated areas inthe contaminated room 302 to give a visual aid to workers as they markand/or decontaminate the contaminated areas. The system 300 may make thedecontamination process more efficient and may reduce radiation exposureto workers.

An exemplary embodiment of a method of identifying radiation inaccordance with one exemplary embodiment is illustrated with referenceto FIG. 19. The method may first start at step 318 in which a detector14 may be deployed into a contaminated room 302 in order to collectradiation data. Moving to step 320, an origin position and theorientation of the detector 14 in the contaminated room 302 may bedetermined. The origin position may be a center 15 of the detector 14,or can be any other location or point from which the relativepositioning of the detector 14 may be determined. The origin positionand orientation of the detector 14 can be obtained through a positiondetermination system 100. Next, the data from the detector 14 may beread in step 322. Obtaining data from detector 14 may be accomplishedvia a telecentric light source 202, aquarium and rotation stage 204, andtelecentric lens 206 arrangement as illustrated in FIG. 11. However, itis to be understood that other methods of obtaining data from thedetector 14 can be employed in step 322.

The method may then move on to step 324 in which radiation data ismapped to objects 140 in a three dimensional computer rendering of thecontaminated room 302. This mapping may be done using input informationobtained in steps 318, 320 and 322 and may potentially includeinformation from detector 14, the position determination system 100, andthe back-projected radiation analyzer and cell evaluator method 200. Theradiation mapping may be to objects 140 such as walls, a ceiling, afloor, a table, a shelf, or another component of the room.

The method may then convert the mapped data of step 324 into a formatcapable of being read by a laser projector as disclosed in step 326.Here, the back-projected radiation analyzer and cell evaluator method200 may be used to generate a text file with a specific format capableof describing how to draw two dimensional line drawings of thecontaminated area. Such a step is disclosed with reference to step 240of FIG. 14 in which output from the method 200 is produced. Any of theoutput in FIG. 14 may be provided to the method in FIG. 19. The dataconverted into the desired format may then be downloaded to the visualillustration system 300. The software implementing step 326 may causethe image that is to be displayed to be an “outline image” in that theboundary lines 310, 312, and 314 will be displayed and created by laserlight while the areas between these lines 310, 312 and 314 will not befilled in by laser light and thus otherwise devoid of light.

Moving next to step 328, the visual illustration system 300 along withthe position determination system 100 may be physically placed withinthe contaminated room 302. This arrangement is shown with reference toFIG. 18. The visual illustration system 300 is located on top of theposition determination system 100, but could be located on any portionof the position determination system 100 or could be completely separatefrom the position determination system 100. Further, it is to beunderstood that in other embodiments the position determination system100 need not be present in step 328 and that the visual illustrationsystem 300 can be placed into the contaminated room 302 by itself.

In step 330 the visual illustration system 300 may be oriented by way ofinput obtained from the position orientation system 100. In this regard,the position orientation system 100 may itself physically orient system300, or system 300 may itself be capable of physically orienting itself.The system 300 could be oriented so that it is placed into the samephysical orientation as the orientation line 138. The system 300 mayobtain orientation data from the system 100 so that system 300 knowswhere the detector 14 is positioned and/or orientated so that the system300 properly displays the projected image 308. Physical parts of thesystem 300 may be moved so that the system 300 is properly oriented viainput obtained from the position orientation system 100.

The system 300 may be placed at the same height as the origin or otherfeature of the system 100. In this regard, an origin point on the system300 may be placed at the same height, or known offset from, a height ofthe system 100 as both are/were placed in the contaminated room 302.However, if the system 300 is not placed at the same height as thesystem 100, a distance sensor may be added to the system 100 todetermine its height placement. In this regard, this information may beprovided to the system 300 so that a user knows where to properly orientthe height of the system 300. Alternatively, the system 300 may havemechanisms capable of adjusting its height, and its height may be setbased upon this input data from system 100.

The method may then execute step 332 in which the visual illustrationsystem 300 adjusts the mapped data based upon position informationprovided by the position orientation system 100. This adjustment may bemade so that scale and aspect ratio of the projected image 308 arecorrect when projected. The projected image 308 can be cast upon anobject 140 such as a wall 304 in the contaminated room 302 in step 334.In step 336, the projected image 308 may be used to permanently markcontamination by the user. Additionally or alternatively, the projectedimage 308 may be used as a guide in the decontamination of thecontaminated room 302.

The visual illustration system 300 can be used to display twodimensional data onto walls, floors, ceilings, or other objects forlocation marking or removal. It is to be understood that radiation needonly be one reason why the visual illustration system 300 can beemployed, and that other reasons besides radiation source marking ordecontamination may result in use of the visual illustration system 300.As such, the visual illustration system 300 can be used for otherpurposes besides radiation.

One exemplary embodiment of the visual illustration system 300 is shownwith reference to FIG. 20. The visual illustration system 300 is acustomized laser projection system. The position determination system100 may provide output of position and orientation information to a CPU338. The position determination system 100 may be physically connectedto the CPU 338 through a wired connection, or through a wirelessconnection, or the data may be input to the CPU 338 by way of a thumbdrive 352 or other mechanism. The output from the position determinationsystem 100 may be magnetic heading, pitch and roll of the orientationline 138, and distance from an origin to objects 140 of the contaminatedroom 302. The output from the position determination system 100 may alsobe the dimensions of the contaminated room 302 and any other objects 140present therein such that the three dimensional model of thecontaminated room 302 is provided to the CPU 338. The CPU 338 may useall of this information to properly scale and distort the “outlineimage” or projected images 308 that are to be displayed so that theymaintain the correct scale and aspect ratio when projected onto the wall304 via the hardware 340. The CPU 338 may include random access memoryand a non-volatile memory and may include pan & tilt control software344 that functions to provide instructions on moving and pivotinghardware according to input data. The pan & tilt control software 344may allow the hardware 340 to properly orient itself via a pan and tiltfeature such that these components implement step 330 of FIG. 18.

The CPU 338 may also include a scan head control module 346 thatfunctions to cause a laser scan head to actuate and display a projectedimage 308. The scan head control module 346 may be provided withinstructions via scan head control software 348 that is also included inthe CPU 338. The CPU 338 may further include a user interface module 350that allows the user to make geometric corrections to the projectedimage 308. Such a module 350 may be helpful if the projected image 308is not properly sized or fitted to the object 140 in question. The CPU338 may include a processor that performs computing functions, avolatile memory for the temporary storage of information, a non-volatilememory for the permanent or long term storage of information, and othercomponents commonly found in a standard desk top computer.

The CPU 338 may include a Pangolin QM2000 PCI card, LD2000 software, andcustom software and may receive the predefined point structures saved ina text file format. This structure may be converted when the system 300is offline into a laser displayable format.

A touch screen monitor 342 may be present and can be in communicationwith the CPU 338. The touch screen monitor 342 may allow the user toinput certain commands that cause the CPU 338 to subsequently performvarious functions for the visual illustration system 300. For example,the touch screen monitor 342 may allow the user to select a particularwall 140 of the contaminated room 302 for display of the projected image308. If the user selects, for example, a “north wall” then the visualillustration system 300 will function to turn on all projected images308 of the north wall while the other walls and objects of thecontaminated room 302 are not provided with their projected images. Thisfeature may be necessary when the visual illustration system 300 is onlycapable of pointing and displaying projected images 308 to one wall at atime. However, in other embodiments, the visual illustration system 300can be so configured that it may display every projected image 308 inthe contaminated room 302. The touch screen monitor 342 allows the userto control which projected images 308 are displayed onto the appropriatewall 140 or object 140. The touch screen monitor 342 may have soft keysthat are left and right arrow buttons that will allow one to sequencethrough images such as north wall, east wall, south wall, west wall,ceiling, floor, and off. Further, if more than one projected image 308is illuminated on a particular object 140, the touch screen monitor 342may allow the user to turn certain ones on or off so that only a singleprojected image 308 is displayed on the object at a particular time.

Aside from selecting a wall 140 or a projected image 308 for display,the touch screen monitor 342 may allow the user to tweak the projectedimage 308 if it is not exactly correct. For example, the touch screenmonitor 342 may allow the user to adjust the projected image 308 viaactuation of soft keys including rotate clockwise, rotate counterclockwise, pitch up, pitch down, roll right, roll left, zoom in, andzoom out.

A thumb drive 352 may be included in the visual illustration system 300that could include image data. The image data may be output from theback-projected radiation analyzer and cell evaluator method 200. Thethumb drive 352 may include the processed information from the detector14 or from the position determination system 100. In other arrangements,information input into the CPU 338 may not come from the thumb drive352, but may instead come from a wireless or hard wired link from themethod 200 or position determination system 100, or may be actuallytyped or otherwise manually input into the CPU 338.

The visual illustration system 300 may include hardware 340 that is incommunication with the CPU 338. One piece of the hardware 340 may be apan & tilt mechanism 354 that receives commands from the pan & tiltcontrol software 344. The pan & tilt mechanism 354 functions to moveother hardware in the vertical and/or horizontal directions and mayfunction to tilt other hardware up and down in a vertical direction orleft and right in a horizontal direction. Information from the positiondetermination system 100 may be used by the pan & tilt control software344 to cause the pan & tilt mechanism 354 to properly orient itself in apan and tilt manner. Again, this information may be magnetic heading,pitch and roll information, but may be other information in otherembodiments. The CPU 338 may be located outside of the contaminated room302 such that the CPU 338 communicates with the hardware 340 through awireless communication. Alternatively, the CPU 338 may be located in thecontaminated room 302 and communicate with the hardware 340 through aphysical, hard wired connection.

The hardware 340 may also include a scan head 356. The scan head 356 caninclude one or more lasers 358. The lasers 358 may be multiple colorlasers so that the projected image 308 may have multiple colors therein.The multiple color lasers 358 may be a red laser and a green laser inaccordance with one exemplary embodiment. Various exemplary embodimentsexist in which from 1-5, from 5-10, or up to 20 different colored lasers358 are present in the scan head 356. The scan head 356 may also includean X-axis scanner 360 and a Y-axis scanner 362. The X-axis scanner 360may be a Cambridge scanner, and the Y-axis scanner 362 may be aCambridge scanner in one embodiment. The X-axis scanner 360 may beresponsible for locating the laser light at the correct location in theX direction, and the Y-axis scanner 362 may be responsible for locatingthe laser light at the proper location in the Y direction. The scan head356 is controlled by a 2 axis driver module 364. The 2-axis drivermodule 364 provides instructions to the X and Y-axis scanners 360 and362 in order to instruct them where to direct the laser light. The2-axis driver module 364 may also function to cause the scan head 356 toactuate the proper laser of the multiple color lasers 358 so that theprojected image 308 is properly displayed. Although shown as beingseparate from the CPU 338, the 2-axis driver module 364 may be a part ofthe CPU 338 in accordance with other exemplary embodiments. The 2-axisdriver module 364 may be located in the contaminated room 302 when theprojected image 308 is displayed, or may be outside of the contaminatedroom 302 such that it wirelessly communicates with the hardware 340.

The projected image 308 displayed by the scan head 356 may be atwo-dimensional, multiple-color line drawing displayed on one surface140 at a time. The projected image 308 may be scaled by the scan head356 and may maintain a proper aspect ratio. The projected image 308 maybe scaled and the aspect ratio of the projected image 308 may bemaintained such that if the projected image 308 were a rectangle withthe same aspect ratio as a wall 140, the laser light would only show atthe edges of the wall 140. Portions of the visual illustration system300, such as the hardware 340, may be placed anywhere on the floor ofthe contaminated room 302. However, these portions may need to be placedsome nominal distance from all of the walls 140 so that the laser lightis able to properly display the projected images 308. The visualillustration system 300 will thus function so that if the projectedimage 308 is a circle, the projected image 308 will look like a circleinstead of an ellipse no matter where in the contaminated room 302 thevisual illustration system 300 is located. Additionally, the diameter ofthe projected circle will be the same if the visual illustration system300 were located close to the wall 140 to which is was projected or ifit were located further from the wall 140 to which the projected circlewas projected. The visual illustration system 300 may be powered by theuse of batteries or may be powered through a standard plug-inconnection.

The hardware 340 may include a 110 VAC compact PCI computer with aPangolin QM scan computer on board with 16-bit DACs. A separate drivermodule 364 may include a power supply and will feed its 2-axis output toa compact XY scanhead by way of an approximately three meter longumbilical. The scan head 356 may have an angular display limited to thecapacity of the scanners which may be +/−30 degrees optical. Class 3 agreen and red lasers may be used with digital color control and blankingsignals provided by the QM board via the 2 axis driver module 364. Thesystem 300 hardware 340 may be configured so that both lasers cannot beon at the same time. The laser output may be a combined 50 mw withdigital color control and blanking signals provided by the QM board withthe 2 axis driver module 364. The laser output may be automatically shutoff via the CPU 338 software or software of the scan head 356 or 2 axisdriver module 364 if there is a scan head failure or if the scan speedfalls below a safe threshold.

The software of the CPU 338 may be Windows based with a Pangolin LD2000scan engine. Wizard 2000 software will have the capability of convertingtext files in proprietary format into generic Pangolin laser viewable 1db format. The text file may contain a sequential specification ofCartesian coordinates and the required display color of thosecoordinates including black for blanking point. The text file mayinclude a header that specifies the total points contained in the imagearray.

The CPU 338 may be arranged so that the scan head control 346 and thescan head control software 348 is Pangolin QM2000 hardware, PangolinLD2000 software, and Holo-Spectra Wizard 2000 software in accordancewith one exemplary embodiment. Further, although disclosed as having apan & tilt mechanism 354 and pan & tilt control software 344, theseelements are not needed in certain exemplary embodiments.

The visual illustration system 300 need not be positioned in the samepoint in the room as the position determination system 100, center 15 ofdetector 14, or origin used by the position determination system 100.Further, the visual illustration system 300 need not be oriented thesame way as the orientation line 138. The visual illustration system 300obtains data on the configuration of the contaminated room 302 and thelocation of contamination in the contaminated room 302. Knowledge of thedimensions of the contaminated room 302 and the location and intensityof contamination allows for this feature. In this regard, so long as thevisual illustration system 300 knows where it is located, it may projectthe projected images 308 properly. However, it may be the case that thevisual illustration system 300 is placed onto the position determinationsystem 100 or otherwise incorporated therewith. The visual illustrationsystem 300 may piggyback onto the position orientation and determinationfeatures of system 100 and thus a repeat of these hardware and softwarefeatures need not be added. As such, the visual illustration system 300may obtain output from system 100 so that the system 300 knows itsposition and orientation within the contaminated room 302.

The visual illustration system 300 may be wrapped in plastic so that itcan be retrieved and reused later considering the fact that the roominto which it is placed will be contaminated with radioactive material.Alternatively, the system 300 can be made inexpensively enough so thatit can be simply disposed of if it becomes contaminated with radioactivematerial.

An alternative exemplary embodiment of the system 300 is shown withreference to FIG. 21. Here, instead of employing the pan & tiltmechanism 354 and associated software 344, the system employs aplurality of scan heads 356 to obtain the desired projected image 308.The various scan heads 356 may be positioned so that they are at anglessufficient to provide coverage to the object 140 or objects 140 of thecontaminated room 302. The system 300 may be capable of rotating thevarious scan heads 356 or raising or lowering same so that they may havesome degree of movement. However, the various scan heads 356 need not becapable of being pivoted or moved in accordance with various exemplaryembodiments.

The hardware 340 includes a plurality of scan heads. As shown, a firstscan head 356 is disclosed, along with an N number of scan heads 366.Any number N of scan heads 366 can be present. For example, from 1-5,from 6-10, or up to 100 additional scan heads 366 can be included. Eachone of the scan heads 366 may include an X-axis scanner 370 and a Y-axisscanner 372. Further, each one of the additional scan heads 366 mayinclude multiple color lasers 368 that may be of the same number andcolors as multiple color lasers 358. The additional scan heads 366,lasers 368, and X and Y-axis scanners 370 and 372 may be configured asthose previously discussed with respect to the scan head 356, lasers358, and X and Y-axis scanners 360 and 362 and a repeat of thisinformation is not necessary. An additional 2-axis driver module 374 maybe provided with each one of the additional scan heads 366 to directfunctioning of the scan heads 366 in a manner similar to that of module364. As such, a repeat of this information is not necessary. Eachadditional scan head N 366 may be provided with its own dedicated t-axisdriver module N 374.

The system 300 in FIG. 21 does not include a pan & tilt mechanism 354and pan & tilt control software 344. However, the CPU 338 is providedwith additional scan head controllers N 376 that function to sendinstructions to their respective 2-axis driver module 374. Each one ofthe additional 2-axis driver modules 374 may have its own dedicatedadditional scan head controller N 376 in the CPU 338. The scan headcontroller N 376 can be configured in a manner previously discussed withrespect to the scan head controller 348, and a repeat of thisinformation is not necessary. The remaining features of system 300 inFIG. 21 may be arranged as those in FIG. 20 and a repeat of thisinformation is not needed. The multiple scan heads 366 can besimultaneously actuated, if appropriate, in order to generate theprojected image 316. As such, any number of scan heads 366 can beactuated at a single time to generate image 316. The scan heads 366 mayprovide coverage to different angles of the object 140 so that the scanheads 366 need not be pivoted or panned in order to accurately createthe projected image 316.

As used herein, the various rooms or contaminated rooms 302 disclosedwith reference to the various methods, systems and apparatuses discussedcan be reactors, fuel and isotope processing facilities, laboratories,hot cells, glove boxes, or isolators. The various rooms or contaminatedrooms 302 can be any room or even an outside area onto which radiationcontamination may be present.

While the present invention has been described in connection withcertain preferred embodiments, it is to be understood that the subjectmatter encompassed by way of the present invention is not to be limitedto those specific embodiments. On the contrary, it is intended for thesubject matter of the invention to include all alternatives,modifications and equivalents as can be included within the spirit andscope of the following claims.

What is claimed is:
 1. A method of identifying the location ofradioactive material in a contaminated room, comprising the steps of:collecting data on the location of radioactive material on an object inthe contaminated room; placing a visual illustration system within thecontaminated room such that the visual illustration system is physicallylocated within the contaminated room; and projecting via the visualillustration system a projected image onto the object that identifies alocation of radioactive material on the object.
 2. The method as setforth in claim 1, further comprising the steps of: obtaining informationon the location of radioactive material in the contaminated room by useof a radiosensitive detector material that is sensitive to radiation;obtaining information on a location and orientation of theradiosensitive detector material in the contaminated room; and obtaininglocation and dimensional information of the object and of additionalobjects in the contaminated room; wherein the step of collecting data isaccomplished via a transfer of the information from the obtaininginformation on the location of radioactive material step, theinformation from the obtaining information on the location andorientation step, and the information from the obtaining location anddimensional information step to the visual illustration system.
 3. Themethod as set forth in claim 1, further comprising the step ofconverting mapped data regarding location and intensity of radiation andlocation and dimensions of the object into a format capable of beingread by a laser projector that includes a text file with a specificformat capable of describing how to draw a two dimensional line drawingof the location of radioactive material on the object.
 4. The method asset forth in claim 1, wherein the projected image is of multiple colorsthat identify the location of different intensities of radioactivematerial on the object.
 5. The method as set forth in claim 4, whereinthe projected image is made of multiple color laser lights such that ahigh radiation intensity boundary is defined by one of the colors oflaser lights, and such that a medium radiation intensity boundary isdefined by a different color of one of the colors of laser lights, andsuch that a low radiation intensity boundary is defined by a differentcolor of one of the colors of laser lights that is different from thehigh and medium radiation intensity boundary colors.
 6. A method ofidentifying the location of radioactive material in a contaminated room,comprising: conducting a radiation survey of the contaminated room;transferring information from the radiation survey to a projector;placing the projector in the contaminated room; and projectinginformation from the radiation survey onto an object in the contaminatedroom.
 7. The method as in claim 6, further comprising determining thelocation of the projector in the contaminated room.
 8. The method as inclaim 6, further comprising projecting information from the radiationsurvey onto an object in the contaminated room in a plurality of colorsthat reflect a plurality of intensities of radiation detected by theradiation survey.
 9. The method as in claim 6, further comprisingmaintaining the projected information from the radiation survey on theobject constant for various positions of the projector in thecontaminated room.
 10. The method as in claim 6, further comprisingadjusting the projected information from the radiation survey based onthe position of the projector in the contaminated room so that theprojected information from the radiation survey onto the object in thecontaminated room remains unchanged.
 11. The method as in claim 6,further comprising marking the object in the contaminated room toreflect the projected information from the radiation survey.
 12. Asystem for identifying the location of radioactive material in acontaminated room, comprising: a projector; a distance sensor; and a CPUoperably connected to the projector and distance sensor; wherein the CPUreceives distance data from the distance sensor and controls an imageprojected by the projector onto an object in the contaminated room. 13.The system as in claim 12, wherein the projector comprises a laserprojector.
 14. The system as in claim 12, wherein the CPU adjusts theimage projected by the projector onto the object in the contaminatedroom based on the position of the projector in the contaminated room.15. The system as in claim 12, further comprising a compass operablyconnected to the CPU, wherein the CPU receives angle data from thecompass and controls the image projected by the projector onto theobject in the contaminated room.
 16. The system as in claim 12, whereinthe CPU adjusts the image projected by the projector onto the object inthe contaminated room based on the orientation of the projector in thecontaminated room.